Information signal recording and reproducing apparatus and recording and reproducing method

1. An information signal recording and reproducing apparatus for selecting an arbitrary region of a recording medium and recording and reproducing, wherein an information signal recorded on said recording medium is constructed by a main signal and additional information which was made correspond to said main signal, said additional information is constructed by time information showing a recording time of said main signal and content information showing the contents of said main signal, and said apparatus comprises: reference information holding means for holding preserving period information of every said content information; and control means for performing processes such that the presence or absence of a vacant region is detected, when said vacant region exists, the signal is recorded into said vacant region, when said vacant region doesn't exist, said additional information of a recorded region is reproduced, an elapsed time of the recorded region is calculated from said time information in said reproduced additional information and present time information, whether the recorded region can be erased or not is decided from said elapsed time and said preserving period information corresponding to said content information in the reproduced additional information, and the signal is recorded to the recorded region which was determined to be erasable.

2. An information signal recording and reproducing apparatus according to claim 1, characterized in that said apparatus has means for inputting said additional information from an outside, and said additional information is inputted and recorded upon recording of said main signal.

3. An information signal recording and reproducing apparatus according to claim 1, characterized in that said additional information is inputted in association with the main signal which is recorded.

4. An information signal recording and reproducing apparatus according to claim 1, characterized in that said main signal and said additional information are recorded to a common recording medium.

5. An information signal recording and reproducing apparatus according to claim 1, characterized in that said main signal and said additional information are recorded to different recording media.

6. An information signal recording and reproducing apparatus according to claim 1, characterized in that said reference information holding means can select or change a condition setting on the basis of an input from an outside.

7. An information signal recording and reproducing apparatus according to claim 1, characterized in that said control means executes a process for deciding whether the signal can be erased or not every process for recording the signal.

8. An information signal recording and reproducing apparatus according to claim 1, characterized in that said control means executes a process for deciding whether the signal can be erased or not when the recording medium is loaded.

9. An information signal recording and reproducing apparatus according to claim 1, characterized in that said control means forms a list in which the erasable regions determined in the recorded region are arranged in accordance with the order corresponding to the positions before and after the time when the signal can be erased.

10. An information signal recording and reproducing apparatus according to claim 1, characterized in that said control means forms a list in which the erasable regions determined in the recorded region are arranged in accordance with the order corresponding to the duration of a period of time when the signal can be erased.

11. An information signal recording and reproducing apparatus according to claim 1, characterized in that in said recording region, a series of lengths of said main signal is set to a unit.

12. An information signal recording and reproducing apparatus according to claim 1, characterized in that in said recording region, a minimum data amount to be recorded and reproduced is set to a unit.

13. An information signal recording and reproducing method of selecting an arbitrary region of a recording medium and recording and reproducing, characterized in that: an information signal recorded on said recording medium is constructed by a main signal and additional information which was made correspond to said main signal, said additional information is constructed by time information showing a recording time of said main signal and content information showing the contents of said main signal; and there are executed processes such that the presence or absence of a vacant region is detected, when said vacant region exists, the signal is recorded into said vacant region, when said vacant region doesn't exist, said additional information of a recorded region is reproduced, an elapsed time of said recorded region is calculated from said time information in the reproduced additional information and present time information, whether the recorded region can be erased or not is decided from said elapsed time and said preserving period information corresponding to said content information in said reproduced additional information, and the signal is recorded into the recorded region which was determined to be erasable.